A Retelling of the prison arc of the manga RIKI-OH! The story follows Saiga Riki-Oh, a young man blessed with inhuman strength. After taking revenge against a yakuza boss who was responsible for the death of his girlfriend, he ends up in a maximum security prison owned by a private organization. The prison is divided into four blocks, each run by a member of prisoners known as the Gang of Four. The first member is a...